Conference Papers
Science Quality and Integrity
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The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
Browse almost 5,000 conference papers authored by our scientists and refine search by topic, location, year, and advanced search.
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A petroleum system model for gas hydrate deposits in northern Alaska
Gas hydrate deposits are common on the North Slope of Alaska around Prudhoe Bay, however the extent of these deposits is unknown outside of this area. As part of a United States Geological Survey (USGS) and the Bureau of Land Management (BLM) gas hydrate research collaboration, well cutting and mud gas samples have been collected and analyzed from mainly industry-drilled wells on the Alaska North
Authors
T.D. Lorenson, Timothy S. Collett, Florence L. Wong
Evidence and biogeochemical implications for glacially-derived sediments in an active margin cold seep
Delineating sediment organic matter origins and sediment accumulation rates at gas hydratebearing and hydrocarbon seeps is complicated by the microbial transfer of 13C-depleted and 14Cdepleted methane carbon into sedimentary pools. Sediment 13C and 14C measurements from four cores recovered at Bullseye vent on the northern Cascadia margin are used to identify methane carbon assimilation into diffe
Authors
John W. Pohlman, Michael Riedel, Ivana Novosel, James E. Bauer, Elizabeth A. Canuel, Charles K. Paull, Richard B. Coffin, Kenneth S. Grabowski, David L. Knies, Roy D. Hyndman, George D. Spence
Laboratory formation of non-cementing, methane hydrate-bearing sands
Naturally occurring hydrate-bearing sands often behave as though methane hydrate is acting as a load-bearing member of the sediment. Mimicking this behavior in laboratory samples with methane hydrate likely requires forming hydrate from methane dissolved in water. To hasten this formation process, we initially form hydrate in a free-gas-limited system, then form additional hydrate by circulating m
Authors
William F. Waite, Peter M. Bratton, David H. Mason
Pockmarks: Self-scouring seep features?
Pockmarks, or seafloor craters, occur worldwide in a variety of geologic settings and are often associated with fluid discharge. The mechanisms responsible for pockmark preservation, and pockmarks? relation to active methane venting are not well constrained. Simple numerical simulations run in 2-and 3-dimensions, and corroborated by flume tank experiments, indicate turbulence may play a role in po
Authors
Laura L. Brothers, Joseph T. Kelley, Daniel F. Belknap, Walter A. Barnhardt, Peter O. Koons
Beaufort Sea deep-water gas hydrate recovery from a seafloor mound in a region of widespread BSR occurrence
Gas hydrate was recovered from the Alaskan Beaufort Sea slope north of Camden Bay in August 2010 during a U.S. Coast Guard Cutter Healy expedition (USCG cruise ID HLY1002) under the direction of the U.S. Geological Survey (USGS). Interpretation of multichannel seismic (MCS) reflection data collected in 1977 by the USGS across the Beaufort Sea continental margin identified a regional bottom simulat
Authors
Patrick E. Hart, John W. Pohlman, T.D. Lorenson, Brian D. Edwards
Unravelling long-term vegetation change patterns in a binational watershed using multitemporal land cover data and historical photography
A significant amount of research conducted in the Sonoran Desert of North America has documented, both anecdotally and empirically, major vegetation changes over the past century due to human land use activities. However, many studies lack coincidental landscape-scale data characterizing the spatial and temporal manifestation of these changes. Vegetation changes in a binational (USA and Mexico) wa
Authors
Miguel L. Villarreal, Laura M. Norman, Robert H. Webb, Diane E. Boyer, Raymond M. Turner
Comparison of main-shock and aftershock fragility curves developed for New Zealand and US buildings
Seismic risk assessment involves the development of fragility functions to express the relationship between ground motion intensity and damage potential. In evaluating the risk associated with the building inventory in a region, it is essential to capture 'actual' characteristics of the buildings and group them so that 'generic building types' can be generated for further analysis of their damage
Authors
S.R. Uma, H. Ryu, N. Luco, A.B. Liel, M. Raghunandan
Structure and dynamics of an upland old- growth forest at Redwood National Park, California
Many current redwood forest management targets are based on old-growth conditions, so it is critical that we understand the variability and range of conditions that constitute these forests. Here we present information on the structure and dynamics from six one-hectare forest monitoring plots in an upland old-growth forest at Redwood National Park, California. We surveyed all stems =20 cm DBH in 1
Authors
Philip J. van Mantgem, John D. Stuart
Assessing effects of changing land use practices on sediment loads in Panther Creek, north coastal California
Revisions to the California Forest Practice Rules since 1974 were intended to increase protection of water quality in streams draining timber harvest areas. The effects of improved timber harvesting methods and road designs on sediment loading are assessed for the Panther Creek basin, a 15.4 km2 watershed in Humboldt County, north coastal California. We compute land use statistics, analyze suspend
Authors
Mary Ann Madej, Greg Bundros, Randy Klein
Entrainment of bed sediment by debris flows: results from large-scale experiments
When debris flows grow by entraining sediment, they can become especially hazardous owing to increased volume, speed, and runout. To investigate the entrainment process, we conducted eight largescale experiments in the USGS debris-flow flume. In each experiment, we released a 6 m3 water-saturated debris flow across a 47-m long, ~12-cm thick bed of partially saturated sediment lining the 31º flume.
Authors
Mark E. Reid, Richard M. Iverson, Matthew Logan, Richard G. LaHusen, Jonathan W. Godt, Julie P. Griswold
Hydrologic conditions and terrestrial laser scanning of post-fire debris flows in the San Gabriel Mountains, CA, U.S.A.
To investigate rainfall-runoff conditions that generate post-wildfire debris flows, we instrumented and surveyed steep, small watersheds along the tectonically active front of the San Gabriel Mountains, California. Fortuitously, we recorded runoff-generated debris-flows triggered by one spatially restricted convective event with 28 mm of rainfall falling over 62 minutes. Our rain gages, nested hil
Authors
Kevin M. Schmidt, M. N. Hanshaw, James F. Howle, Jason W. Kean, Dennis M. Staley, Jonathan D. Stock, Gerald W. Bawden
Spatially explicit shallow landslide susceptibility mapping over large areas
Recent advances in downscaling climate model precipitation predictions now yield spatially explicit patterns of rainfall that could be used to estimate shallow landslide susceptibility over large areas. In California, the United States Geological Survey is exploring community emergency response to the possible effects of a very large simulated storm event and to do so it has generated downscaled p
Authors
Dino Bellugi, William E. Dietrich, Jonathan D. Stock, Jim McKean, Brian Kazian, Paul Hargrove
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Energy and Minerals Mission Area, Natural Hazards Mission Area, Energy Resources Program, Groundwater and Streamflow Information Program, Landslide Hazards Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Geologic Hazards Science Center, Geology, Minerals, Energy, and Geophysics Science Center